共查询到20条相似文献,搜索用时 31 毫秒
1.
Kazuyuki Nagamatsu 《Journal of biomolecular structure & dynamics》2013,31(4):729-739
Abstract Fluorophore of proflavine was introduced onto the 3′-terminal ribose moiety of yeast tRNAPhe. The distance between the fluorophore and the fluorescent Y base in the anticodon of yeast tRNAPhe was measured by a singlet-singlet energy transfer. Conformational changes of tRNAPhe with binding of tRNAGlu 2, which has the anticodon UUC complementary to the anticodon GAA of tRNAPhe, were investigated. The distance obtained at the ionic strength of 100 mM K+ and 10 mM Mg2+ is very close to the distance from x-ray diffraction, while the distance obtained in the presence of tRNAGlu 2 is significantly smaller. Further, using a fluorescent probe of 4-bromomethl-7-methoxycoumarin introduced onto pseudouridine residue Ψ55 in the TΨC loop of tRNAPhe, Stern-Volmer quenching experiments for the probe with or without added tRNAGlu 2were carried out. The results showed greater access of the probe to the quencher with added tRNAGlu 2. These results suggest that both arms of the L-shaped tRNA structure tend to bend inside with binding of tRNAGlu 2 and some structural collapse occurs at the corner of the L-shaped structure. 相似文献
2.
CHU‐YIN LIN WEN‐WEN LIN HSIAO‐WEI KAO 《Zoological Journal of the Linnean Society》2012,165(3):521-533
The mackerel icefish (Champsocephalus gunnari Lönnberg, 1905) is a ray‐finned fish living in the Southern Ocean around Antarctica. We sequenced the complete mitochondrial (mt) genome of the mackerel icefish and a segment from cytochrome b to the control region (CR) in 32 individuals. The mt genome of the mackerel icefish was rearranged, containing two nicotinamide adenine dinucleotide (reduced form) dehydrogenase subunit 6 (ND6), two tRNAGlu, and two CRs. However, variations in numbers of ND6 and tRNAGlu were observed amongst individuals. These variations included type 1 (containing two ND6 and two tRNAGlu), type 2 (containing one ND6, one incomplete ND6, and one tRNAGlu), and type 3 (containing one ND6 and one tRNAGlu). The gene orders of types 1 and 2, and variations in numbers of ND6 and tRNAGlu were not previously found in any Antarctic notothenioids, whereas type 3 is the same as that of Racovitzia glacialis. Phylogenetic analyses of CR DNA sequences showed that duplicated CRs of the same species formed a monophyletic group, suggesting that duplication of CRs occurred in each species. The frequent duplication of mt genomes in Antarctic notothenioids is an unusual feature in vertebrates. We propose that interspecific hybridization and impairment of mismatch repair might account for the high frequency of gene duplications and rearrangement of mt genomes in Antarctic notothenioids. 相似文献
3.
N. Morrison J. P. Goddard D. H. Ledbetter E. Boyd D. Bourn J. M. Connor 《Human genetics》1991,87(2):226-230
Summary A cluster of tRNA genes (tRNA
UAG
Leu
, tRNA
CUG
Gln
, tRNA
UUU
Lys
, tRNA
UCU
Arg
) and an adjacent tRNA
GCC
Gly
have been assigned to human chromosome 17p12–p13.1 by in situ hybridization using a 4.2 kb human DNA fragment for tRNALeu, tRNAGln, tRNALys, tRNAArg, and, for tRNAGly, 1.3 kb and 0.58 kb human DNA fragments containing these genes as probes. This localization was confirmed and refined to 17p13.100–p13.105 using a somatic cell hybrid mapping panel. Preliminary experiments with the biotiny lated tRNA Leu, Gln, Lys, Arg probe and metaphase spreads from other great apes suggest the presence of a hybridization site on the long arm of gorilla (Gorilla gorilla) chromosome 19 and the short arm of orangutan (Pongo pygmaeus) chromosome 19 providing further support for homology between HSA17, GGO19 and PPY19. 相似文献
4.
M. Keller G. Burkard H.J. Bohnert M. Mubumbila K. Gordon A. Steinmetz D. Heiser E.J. Crouse J.H. Well 《Biochemical and biophysical research communications》1980,95(1):47-54
Hybridization studies of Euglena chloroplast 125I-labeled tRNAs to restriction fragments of Euglena chloroplast DNA have shown that the spacer between the 16S and 23S rRNA genes, in two and possibly all three of the ribosomal DNA units, contains genes for tRNAIle and tRNAAla, whereas a tRNA gene (for either tRNATrp or tRNAGlu) is located before probably all four 16S rRNA genes present on the chloroplast DNA molecule. 相似文献
5.
The complete nucleotide sequence of the mitochondrial genome was determined for a conger eel, Conger myriaster (Elopomorpha: Anguilliformes), using a PCR-based approach that employs a long PCR technique and many fish-versatile primers.
Although the genome [18,705 base pairs (bp)] contained the same set of 37 mitochondrial genes [two ribosomal RNA (rRNA), 22
transfer RNA (tRNA), and 13 protein-coding genes] as found in other vertebrates, the gene order differed from that recorded
for any other vertebrates. In typical vertebrates, the ND6, tRNAGlu, and tRNAPro genes are located between the ND5 gene and the control region, whereas the former three genes, in C. myriaster, have been translocated to a position between the control region and the tRNAPhe gene that are contiguously located at the 5′ end of the 12S rRNA gene in typical vertebrates. This gene order is similar
to the recently reported gene order in four lineages of birds in that the latter lack the ND6, tRNAGlu, and tRNAPro genes between the ND5 gene and the control region; however, the relative position of the tRNAPro to the ND6–tRNAGlu genes in C. myriaster was different from that in the four birds, which presumably resulted from different patterns of tandem duplication of gene
regions followed by gene deletions in two distantly related groups of organisms. Sequencing of the ND5–cyt b region in 11 other anguilliform species, representing 11 families, plus one outgroup species, revealed that the same gene
order as C. myriaster was shared by another 4 families, belonging to the suborder Congroidei. Although the novel gene orders of four lineages of
birds were indicated to have multiple independent origins, phylogenetic analyses using nucleotide sequences from the mitochondrial
12S rRNA and cyt b genes suggested that the novel gene orders of the five anguilliform families had originated in a single ancestral species.
Received: 13 July 2000 / Accepted: 30 November 2000 相似文献
6.
By cloning and sequencing 3.4 kilobases of snow goose mtDNA we found that the ND5 gene is followed by the genes for cytochrome b, tRNAThr, tRNAPro, ND6, tRNAGlu, the control region, tRNAPhe, and srRNA. This order is identical to that of chicken, quail, and duck mtDNA but differs from that of mammals and a frog (Xenopus). The mean extent of difference due to base substitution between goose and chicken is generally closer to the same comparison between rat and mouse but less than that between human and cow. For one of the nine regions compared (tRNAGlu), the bird differences appear to be anomalous, possibly implicating altered functional constraints. Within the control region, several short sequences common to mammals are also conserved in the birds. Comparison of the goose control region with that of quail and chicken suggests that a sequence element with similarity to CSB-1 duplicated once prior to the divergence of goose and chicken and again on the lineage leading to chicken. Between goose (or duck) and chicken there are four times more transversions at the third positions of fourfold-degenerate codons in mitochondrial than in nuclear genes.Abbreviations CSB
conserved sequence block
- cytb
cytochrome b
- ND
NADH dehydrogenase
- srRNA
small-subunit ribosomal RNA
Deceased July 21, 1991
Correspondence to: T.W. Quinn at the University of Denver 相似文献
7.
8.
The glutaminyl-tRNA synthetase (GlnRS) enzyme, which pairs glutamine with tRNAGln for protein synthesis, evolved by gene duplication in early eukaryotes from a nondiscriminating glutamyl-tRNA synthetase (GluRS) that aminoacylates both tRNAGln and tRNAGlu with glutamate. This ancient GluRS also separately differentiated to exclude tRNAGln as a substrate, and the resulting discriminating GluRS and GlnRS further acquired additional protein domains assisting function in cis (the GlnRS N-terminal Yqey domain) or in trans (the Arc1p protein associating with GluRS). These added domains are absent in contemporary bacterial GlnRS and GluRS. Here, using Saccharomyces cerevisiae enzymes as models, we find that the eukaryote-specific protein domains substantially influence amino acid binding, tRNA binding and aminoacylation efficiency, but they play no role in either specific nucleotide readout or discrimination against noncognate tRNA. Eukaryotic tRNAGln and tRNAGlu recognition determinants are found in equivalent positions and are mutually exclusive to a significant degree, with key nucleotides located adjacent to portions of the protein structure that differentiated during the evolution of archaeal nondiscriminating GluRS to GlnRS. These findings provide important corroboration for the evolutionary model and suggest that the added eukaryotic domains arose in response to distinctive selective pressures associated with the greater complexity of the eukaryotic translational apparatus. We also find that the affinity of GluRS for glutamate is significantly increased when Arc1p is not associated with the enzyme. This is consistent with the lower concentration of intracellular glutamate and the dissociation of the Arc1p:GluRS complex upon the diauxic shift to respiratory conditions. 相似文献
9.
We have isolated three independent clones for nuclear elongator tRNAMet genes from an Arabidopsis DNA library using a tRNAMet-specific probe generated by PCR. Each of the coding sequences for tRNAMet in these clones is identical and is interrupted by an identical 11 bp long intervening sequence at the same position in the anticodon loop of the tRNA. Their sequences differ at two positions from the intron in a soybean counterpart. Southern analysis of Arabidopsis DNA demonstrates that a gene family coding for tRNAMet is dispersed at at least eight loci in the genome. The unspliced precursor tRNAMet intermediate was detected by RNA analysis using an oligonucleotide probe complementary to the putative intron sequence. In order to know whether introns commonly interrupt plant tRNAMet genes, their coding sequences were PCR-amplified from the DNAs of eight phylogenetically separate plant species. All 53 sequences determined contain 10 to 13 bp long intervening sequences, always positioned one base downstream from the anticodon. They can all be potentially folded into the secondary structure characteristic for plant intron-containing precursor tRNAs. Surprisingly, GC residues are always present at the 5-distal end of each intron. 相似文献
10.
Li Z Liu Y Yang L Wang S Guan MX 《Biochemical and biophysical research communications》2008,367(4):906-911
Mutations in mitochondrial DNA have been associated with cardiovascular disease. We report here the clinical, genetic, and molecular characterization of one three-generation Han Chinese family with maternally transmitted hypertension. All matrilineal relatives in this family exhibited the variable degree of hypertension at the age at onset of 36 to 56 years old. Sequence analysis of the complete mitochondrial DNA in this pedigree revealed the presence of the known hypertension-associated tRNAIle A4295G mutation and 33 other variants, belonging to the Asian haplogroup D4j. The A4295G mutation, which is extraordinarily conserved from bacteria to human mitochondria, is located at immediately 3′ end to the anticodon, corresponding to conventional position 37 of tRNAIle. The occurrence of the A4295G mutation in several genetically unrelated pedigrees affected by cardiovascular disease but the absence of 242 Chinese controls strongly indicates that this mutation is involved in the pathogenesis of cardiovascular disease. Of other variants, the tRNAGlu A14693G and ND1 G11696A mutations were implicated to be associated with other mitochondrial disorders. The A14693G mutation, which is a highly conserved nucleoside at the TψC-loop of tRNAGlu, has been implicated to be important for tRNA structure and function. Furthermore, the ND4 G11696A mutation was associated with Leber’s hereditary optic neuropathy. Therefore, the combination of the A4295G mutation in the tRNAIle gene with the ND4 G11696A mutation and tRNAGlu A14693G mutation may contribute to the high penetrance of hypertension in this Chinese family. 相似文献
11.
Summary Eight transfer RNA (tRNA) genes which were previously mapped to five regions of the Pisum sativum (pea) chloroplast DNA (ctDNA) have been sequenced. They have been identified as tRNAVal(GAC), tRNAAsn(GUU), tRNAArg(ACG), tRNALeu(CAA), tRNATyr(GUA), tRNAGlu(UUC), tRNAHis(GUG), and tRNAArg(UCU) by their anticodons and by their similarity to other previously identified tRNA genes from the chloroplast DNAs of higher plants or from E. gracilis. In addition,two other tRNA genes, tRNAGly (UCC) and tRNAIle(GAU), have been partially sequenced. The tRNA genes are compared to other known chloroplast tRNA genes from higher plants and are found to be 90–100% homologous. In addition there are similarities in the overall arrangement of the individual genes between different plants. The 5 flanking regions and the internal sequences of tRNA genes have been studied for conserved regions and consensus sequences. Two unusual features have been found: there is an apparent intron in the D-loop of the tRNAGly(UCC), and the tRNAGlu(UUC) contains GATTC in its T-loop. 相似文献
12.
Mouse genomic DNA harboring the full coding sequence of cyclin G1 was cloned and analyzed. The locations of five coding exons and the intron–exon boundary sequences were found to be conserved between the mouse and the human genes. Two putative binding sites for thep53tumor suppressor gene product were found around the first exon: one was located in the 5′ regulatory region, and the other was in the first intron. The mouse cyclin G1 gene was mapped to bands A5 to B1 of chromosomes 11 (11A5–B1) by FISH using genomic DNA clone as a biotinylated probe. The location of mouse cyclin G1 is syntenic to that of its human homologue, which we previously mapped to 5q32–q34 of chromosome 5. An additional faint signal was detected on chromosome 4 (4B1–C2), probably indicating the presence of a cyclin G1-related gene or pseudogene in the mouse genome. 相似文献
13.
Jacques Dainat F. de Balbian Verster R. Zand O. Z. Sellinger 《Neurochemical research》1979,4(5):557-565
The activity of tRNA methyltransferases present in the cerebellum of 6- and 21-day-old nonicteric and icteric Gunn rats was compared using purifiedE. coli tRNAs as substrates. At 6 days the tRNA methyltransferases of the icteric animals were significantly more effective in methylating tRNAGlu
2 and tRNAPhe than were those of their nonicteric counterparts. This relationship reversed itself at 21 days. The action of the tRNA methyltransferases from the 6-day-old icteric animals led to higher proportions of 1-methyladenine in tRNAGlu
2 and tRNAPhe than were obtained using the corresponding enzymes of the nonicteric animals. The proportion ofN
2-methylguanine was also higher, yet only in tRNAfMet and not in tRNAPhe. The study reveals much more extensive fluctuations in the activity and in the substrate recognition specificity among the cerebellar tRNA methyltransferases of the icteric than among those of the nonicteric controls during the crucial 6–21 day period of cerebellar development. 相似文献
14.
Ana Cristina Gomes Anna J. Kordala Rita Strack Xiaoyun Wang Renaud Geslain Kamila Delaney Wesley C. Clark Robert Keenan Tao Pan 《RNA (New York, N.Y.)》2016,22(3):467-476
In mammalian cells under oxidative stress, the methionyl-tRNA synthetase (MetRS) misacylates noncognate tRNAs at frequencies as high as 10% distributed among up to 28 tRNA species. Instead of being detrimental for the cell, misincorporation of methionine residues in the proteome reduces the risk of oxidative damage to proteins, which aids the oxidative stress response. tRNA microarrays have been essential for the detection of the full pattern of misacylated tRNAs, but have limited capacity to investigate the misacylation and mistranslation mechanisms in live cells. Here we develop a dual-fluorescence reporter to specifically measure methionine misincorporation at glutamic acid codons GAA and GAG via tRNAGlu mismethionylation in human cells. Our method relies on mutating a specific Met codon in the active site of the fluorescent protein mCherry to a Glu codon that renders mCherry nonfluorescent when translation follows the genetic code. Mistranslation utilizing mismethionylated tRNAGlu restores fluorescence in proportion to the amount of misacylated tRNAGlu. This cellular approach works well for both transient transfection and established stable HEK293 lines. It is rapid, straightforward, and well suited for high-throughput activity analysis under a wide range of physiological conditions. As a proof of concept, we apply this method to characterize the effect of human tRNAGlu isodecoders on mistranslation and discuss the implications of our findings. 相似文献
15.
16.
17.
The initiator methionine transfer RNA (tRNAf
Met) gene was identified on a 347 bpEco RI-Hind III DNA fragment of the potato mitochondrial (mt) genome. The sequence of this gene shows 1 to 7 nucleotide differences with the other plant mt tRNAsf
Met or tRNAf
Met genes studied so far. Whereas the tRNAf
Met gene is present as a single copy in the potato mt genome, a tRNA pseudogene corresponding to 60% of a complete tRNA (from the 5 end to the variable region) and located at 105 nucleotides upstream of the tRNAf
Met gene on the opposite strand was shown to be repeated at least three times. Furthermore, the physical environment of the tRNAf
Met gene in the mt genome is very different among plants, which suggests that the tRNAf
Met gene region has often been implicated in recombination events of plant mt genomes leading to important rearrangements in gene order. 相似文献
18.
Assignment of anonymous DNA probes to specific intervals of human chromosomes 16 and X 总被引:8,自引:0,他引:8
V. J. Hyland K. E. W. Fernandez D. F. Callen R. N. MacKinnon E. Baker K. Friend G. R. Sutherland 《Human genetics》1989,83(1):61-66
Summary Anonymous DNA probes mapping to human chromosome 16 and the distal region of the human X chromosome were isolated from a genomic library constructed using lambda EMBL3 and DNA from a mouse/human hybrid. The hybrid cell contained a der(16)t(X;16)(q26;q24) as the only human chromosome. Fifty clones were isolated using total human DNA as a hybridisation probe. Forty six clones contained single copy DNA in addition to the repetitive DNA. Pre-reassociation with sonicated human DNA was used to map these clones by a combination of Southern blot analysis of a hybrid cell panel containing fragments of chromosomes 16 and X and in situ hybridisation. One clone mapped to 16pter 16p13.11, one clone to 16p13.316p13.11, four clones to 16p13.316p13.13, two clones to 16p13.1316p13.11, one clone to 16p13.11, seven clones to 16p13.1116q12 or 16q13, four clones to 16q12 or 16q13, three clones to 16q1316q22.1, four clones to 16q22.10516q24, and nineteen clones to Xq26Xqter. Two clones mapping to 16p13 detected RFLPs. VK5 (D16S94) detected an MspI RFLP, PIC 0.37. VK20 (D16S96) detected a TaqI RFLP, PIC 0.37 and two MspI RFLPs, PIC 0.30 and 0.50. The adult polycystic kidney disease locus (PKD1) has also been assigned to 16p13. The RFLPs described will be of use for genetic counselling and in the isolation of the PKD1 gene. Similarly, the X clones may be used to isolate RFLPs for genetic counselling and the isolation of genes for the many diseases that map to Xq26qter. 相似文献
19.
Mitochondrial glutamyl-tRNA isolated from mitochondria of Saccharomyces cerevisiae was separated into two distinct species by re versed-phase chromatography. The migration of the two mitochondrial glutamyl-tRNAs (tRNAIGlu and tRNAIIGlu) differed from that of two glutamyl-tRNA species found in the cytoplasm of a mitochondrial DNA-less petite strain. Both mitochondrial tRNAs hybridized with mitochondrial DNA. Three lines of evidence demonstrate that mitochondrial tRNAIGlu and tRNAIIGlu are transcribed from different mitochondrial cistrons. First the level of hybridization of a mixture of the two tRNAs to mitochondrial DNA was equal to the sum of the saturation hybridization levels of each glutamyl-tRNA alone. Second, the two mitochondrial glutamyl-tRNAs did not compete with each other in hybridization competition experiments. Finally the tRNAs showed individual hybridization patterns with different petite mitochondrial DNAs.Hybridization of the tRNAs to mitochondrial DNA of genetically defined petite strains localized each tRNA with respect to antibiotic resistance markers. The two glutamyl-tRNA cistrons were spatially separated on the genetic map. 相似文献
20.
Josette Derré Oliver Kemper Dorra Cherif Yaron Nophar Roland Berger David Wallach 《Human genetics》1991,87(2):231-233
Summary The gene coding for the type I (p55) tumor necrosis factor receptor (TNF-R1) has been localized on human chromosome 12, band 12p13.2, by in situ hybridisation using a biotinylated genomic probe. 相似文献